This application relates generally to a method of measuring tip erosion of a turbine blade during development and testing of the turbine blade.
During operation of a gas turbine engine, a turbine blade can tilt or expand due to creep (because of temperature and centrifugal forces). When a tip of the turbine blade rubs against a casing of the gas turbine engine, the tip can erode over time. It is important for the turbine blade to have a proper length to reduce wear at the tip while still providing a seal between the tip and the casing. During development of the gas turbine engine and the turbine blade, the gas turbine engine must be disassembled to access the hardware and the turbine blade to measure and determine any erosion, rub and tilt of the tip of the turbine blade, which is costly.
In one prior gas turbine engine, a seal serration part at a tip of a turbine blade includes a single notch. Over time and during normal operation of the gas turbine engine, the seal serration part rubs against a case to wear the seal serration part until the notch is eventually eliminated from the tip. When it is visually determined that the notch is eliminated, this indicates that the turbine blade is approaching fracture due to creep and must be replaced.